Narrative:

We had to do a security check; so I thought it was the first flight of the day and I proceeded to start engine #1. Once completing the start the captain asked me why I started #1; I explained that I thought it was a first flight and wanted to do the first flight checks; he informed me that the aircraft had already flown and didn't need a first flight check; but to just leave #1 engine started and we would go out on that and turn the hydraulics to on so we have the brakes. We ran the takeoff checks and we noticed the T/O config ok and all instruments were in the green. Once we started the #2 engine and ran the checks we were cleared onto runway xx and cleared for takeoff. After we got into the air we got a positive rate of climb and put the gear up; at about 500' the captain began to tell me; 'uh; rudder; rudder help.' I didn't realize at this point what was happening and tried to get clarification; that is when he said; 'rudder' again. That is when I looked down at the pfd and noticed the plane in a slight right bank with the rudder out of trim. I then noticed the rudder trim was at a full right deflection. Once I noticed this I put the rudder trim back into the neutral position and the aircraft started operating normally and the captain brought the autopilot on. Once we corrected the problem the aircraft operated normally and we continued to climbout and switched over to departure. During the climbout the captain decided to call maintenance; I thought it was a good idea since we were still in radio range. I took the radios and the aircraft; once the captain was in contact with maintenance he explained the problem to them and they asked us to continue on to our destination and write up the problem there. After the captain and I discussed the situation further we decided to return to the field since he was a little shaken from the incident and both of us were not comfortable taking the aircraft all the way up to 30;000 ft and possibly having the problem happen again. We then informed ATC we wanted to return to our departure airport and they vectored us back to the field. We contacted dispatch for landing distance and maintenance about the overweight landing. Dispatch informed us we needed about 4500 ft of runway to land; and maintenance said an overweight landing was fine as long as we didn't touch down at more that 300 feet per minute. Once we got the aircraft set up for landing the captain declared an emergency with ATC and informed them we were ready for the approach. We continued to the field landed at about 100 feet per minute without incident.

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Original NASA ASRS Text

Title: CL65 flight crew experienced full right rudder trim shortly after takeoff. Reset trim and decided to return to the departure airport for an overweight landing and a maintenance inspection.

Narrative: We had to do a security check; so I thought it was the first flight of the day and I proceeded to start engine #1. Once completing the start the Captain asked me why I started #1; I explained that I thought it was a first flight and wanted to do the first flight checks; he informed me that the aircraft had already flown and didn't need a first flight check; but to just leave #1 engine started and we would go out on that and turn the Hydraulics to ON so we have the brakes. We ran the Takeoff checks and we noticed the T/O Config OK and all instruments were in the green. Once we started the #2 engine and ran the checks we were cleared onto runway XX and cleared for takeoff. After we got into the air we got a positive rate of climb and put the gear up; at about 500' the Captain began to tell me; 'uh; rudder; rudder help.' I didn't realize at this point what was happening and tried to get clarification; that is when he said; 'rudder' again. That is when I looked down at the PFD and noticed the plane in a slight right bank with the rudder out of trim. I then noticed the rudder trim was at a full right deflection. Once I noticed this I put the rudder trim back into the neutral position and the aircraft started operating normally and the Captain brought the autopilot on. Once we corrected the problem the aircraft operated normally and we continued to climbout and switched over to departure. During the climbout the Captain decided to call maintenance; I thought it was a good idea since we were still in radio range. I took the radios and the aircraft; once the Captain was in contact with maintenance he explained the problem to them and they asked us to continue on to our destination and write up the problem there. After the Captain and I discussed the situation further we decided to return to the field since he was a little shaken from the incident and both of us were not comfortable taking the aircraft all the way up to 30;000 FT and possibly having the problem happen again. We then informed ATC we wanted to return to our departure airport and they vectored us back to the field. We contacted dispatch for landing distance and maintenance about the overweight landing. Dispatch informed us we needed about 4500 FT of runway to land; and maintenance said an overweight landing was fine as long as we didn't touch down at more that 300 feet per minute. Once we got the aircraft set up for landing the Captain declared an emergency with ATC and informed them we were ready for the approach. We continued to the field landed at about 100 feet per minute without incident.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.